Oxidized dimer of 9,11-linolo-diricinolein and method of making same



Patented Aug. 26, 1947 UNITED STATES PATENT OFFICE OXIDIZED DIMER OF 9,11-LINOLO-DIBICIN- OLEIN AND METHOD OF MAKING SAME Melvin De Groote, St. Louis, Mo., assignor to Petrolite Corporation, Ltd., Wilmington, Del, a corporation of Delaware No Drawing. Original application July 13, 1945,

Serial No. 604,991. Divided and this application May 17, 1946, Serial No. 670,533

Claims. (01. 260-406) 1 2 This invention relates to certain new chemical Dec. 13, 1938, to Schwarcman; No. 2,195,225, products or compounds and to the manufacture dated Mar. 26, 1940, to Priester; No. 2,209,065, of same, my present application being a division dated July 23, 1940, to Pelikan; No. 2,212,385,

of my co-pending application Serial No. 604,991, dated Aug. 30, 1940, to Brod; No. 2,226,830, dated fi1edJu1y13,1945. 5 Dec. 31, 1940, to Priester; No. 2,226,831, dated One object of my invention is to provide new Dec. 31, 1940, to Priester; No. 2,261,663, dated chemical products or compounds that are par- Nov. 4, 1941, to Rheineck; No. 2,336,186, dated ticularly adapted for use as a demulsifier in the Dec. 7, 1943, to Nessler; No. 2,351,444, dated I resolution of crude oil emulsions, but which are June 13, 1944, to Miller; and No. 2,246,768, dated also adapted for various other uses, as hereinafter June 24, 1941, to Ubben.

b d- The mixed isomers may be treated so as to Another object of my invention is to provide convert the unconjugated isomer into the cona Practical method o making the said chemical jugated isomer. This isomerization reaction may products or compounds. be indicated thus:

The new chemical products herein described, particularly when employed as a demulsifier, H H H 11 consists of an oxidized dimer of 9,11-linolo-diricinolein. Oxidation is by means of a gaseous (13) I oxygen-containing medium, particularly moist H or dry air, and is conducted in the manner com- (9,12-lino1eic acid) monly used to blow or oxidize castor oil or the H H H E like, in the production of blown castor oil. The I I l I conventional dehydration of castor oil or ricin- ?'Z fififigfig oleic acid, or some other ester, results in the H formation of a diene acid with the probability (elmnoleic acid) that two reactions ordinarily go to approximately v the same degree. These reactions may be illus- Patents ex mplifying isomerization pro.- lira/Bed n the fo lo i m cedure of the kind indicated, see the following: No. 2,185,414, dated Jan. 2, 1940, to McKinney; Reactw 1 No, 2,242,230, dated May 20, 1941, to Burr; and Jill I? 1 1 1 1 E E No. 2,350,583, dated June 6, 1944, to Bradley. 7 9,11-linoleic acid of approximately 80% to 85 o Q f f 1% (CHMOOH 8*) purity is obtainable in the op market and also iii OH: H available in the 'form of the ethyl or methyl I ester.

Ignoring matters of cost, I prefer to prepare l I l the monomeric mixed glyceride from this par- CH3(CH2)'(1C3)CO-O (3) (OH2)7COOH H2O ticular product. Methyl or ethyl ricinoleate,

H which can be prepared in the usual manner or (9,12-1inoleic acid) purchased in the open market, is reacted in the R 2 customary manner with glycerol monochlorohyw drin, using two moles of the ester for one mole of T the chlorohydrin. The reaction may be indicated 011mm ioooo =c om 1o00H thus: 1 o) 9) i H OH i caHaoHco 0011, H OCH I H H H H H CnHaiQHGO OCHa H OCH wiu'mleimm) The 9,11-l in0leic acid is converted into the an- United States patents which illustrate this hydrous sodium salt and reacted mole for mole procedure, are the following: No. 2,140,271, dated with the above intermediat in the presence of anhydrous alcohol, or some other suitable solvent. This reaction may be indicated thus:

CI'ZHQQOHOOO I ,H,Ee1+ Na'iO 0.0171131 CHHMO Other alternate procedures may be used, and

particularly some in which the percentage of mixed glyceride is not as high in the product obtained by the described procedure, but still sufliciently high for the manufacture of valuable products for the employment of processes herein described.

In regard to the above esterification procedure or alternate procedure, see the comprehensive article entitled Polyhydric alcohol esters of fatty acids, in Chemical Reviews, volume 3, No. 3, at page 257.

The polymerization of the diene acid is conducted in th same identical manner employed for the polymerization of the methyl ester. The polymerization of the methyl ester is described in various patents, as, for example: U. S. Patent No. 2,325,040, dated July 27, 1943, to Cook et al.; No. 2,347,562, dated Apr. 25, 1944, to Johnston;- and No, 2,357,839, dated Sept. 12, 1944, to Evans et al.

The dimerization of the methyl ester may be,

indicated in the following manner:

' Heat 2 mole methyl ester 9,11- octadecadieni c acid (originally present and/or formed by isomerlzation of M2 isomer) (See U. S. Patent No. 2,347,562, dated Apr. 25, 1944, to Johnson, above mentioned.)

In polymerization of polyene acid esters, it has been found that temperatures between about 250 C. and about 350 C. are suitable for the polymerization. The time required for this polymerization varies not only with the temperature, but with the acid and the particular ester which is used. Generally, a period of from about one-half hour to about 50 hours is suitable, and in most instances, the polymerization may be effected in not over 12 hours. If a conjugated unsaturated ester, such as the methyl ester of eleostearic acid be employed, a sufficient degree of polymerization may be obtained within one-half to one hour at about 300 0., whereas, the methyl linolenates peratures and/or shorter period of time than mately 250 C., and, as a result of a somewhat lower'temperature, it is sometimes desirable to use a longer time period for isomerization, for instance, a time period as long as twenty-four to forty-eight hours.

Other means for inducing or hastening or catalyzing polymerization of the above described reactants are well known. See, fOr example, U. S. Patent No. 2,207,686, dated July 9, 1940, to Schwarcman.

In any event, any suitable procedure is used to prepare the mixed glyceride, which has the following formula:

Such mixed glyceride is then dimerized in the manner previously described to produce the dimer of the following formula:

, An examination of the preceding formula immediately suggests additional procedures for producing the dimer of the mixed glyceride. For instance, a raw material which can be readily prepared or purchased in the open market is diricinolein. The formula for such product, ignoring isomeric forms, is, of course:

It becomes obvious that if two moles of diricinolein could be reacted with one mole of the dimeric acid which has been previously depicted in the form of a methyl ester, one would then obtain the dimerized mixed glyceride previously described. The objection to such procedure, however, is that reaction cannot be limited to the hydroxyl attached to the glycerol residue, and, in fact, may involve the ricinoleyl hydroxyl radical. Thus, such procedure, although giving fair yields, also gives admixture with other products which preferably are avoided. However, if the methyl ester or ethyl ester of the dimeric acid is used so esterification involves the elimination of the methyl or ethyl alcohol, then and in that event, the reaction appears to be limited largely to involving the glycerol hydroxyl.

Another procedure which immediately suggests itself in formation of the monomeric mixed glyceride, is the procedure commonly referred to as re-esterification, cross-esterification or transesterification. Such procedure iswell known, and in essence, would involve, for example, mixing two moles of triricinolein with one mole of the total or complete glyceride of 9,11-1inoleic acid. Such migration of the acyl radicals takes place at a temperature below the pyrolytic point of triricinolein, and in the presence of an alkaline catalyst. The suitable temperature is approxi-- mately 250 0., or slightly less, and the time required maybe comparatively long, for instance, 36-to 72' hours. V

In any event, one obtains the dimerized mixed glyceride by any suitable procedure, and the product employed shouldpreferably contain at least 65% orsmore of'the dimerized mixed. glyceride; some of the procedures above enumerated will yield a product markedly in excess of this value. Such mixed'glyceride, if carefully prepared, has a viscosity approximately that of castor oil, or slightly b-lown castor oil, a distinctly darker color, and perhaps a less pleasant odor. The chemical constants, such as molecular weight; iodine number, hydroxyl number and saponification value, approximate the calculated theoretical value. It is to be noted that: this intermediateisnot: claimed herein. per so.

It is wellknownthatricinoleic acid compounds, particularly castor oil, canbe oxidized in, various ways. Thisv is usually accomplishedby: subjecting a ricinoleic compound to treatment such as blowing with a suitably gaseous oxidizing medium, e. g., air, oxygen,. ozone, orozonizedair. Such oxidation is commonly carried out. at ordinary or: superatmosphericpressure (up. to. about 200 lbs. per square inch) either moist or dry;. and in the. presence or. absence of. a catalyst,v such as lead'oleate, cobalt. linoleate, or manganese oleate,

or suchfas alpha-pineneor. linseed oil,v etc. Care,

should be taken, however, not to permittemperaturexrise such that excessive pyrolytic decomposition would, take place. The oxidation, may be vigorous, asby vigorous blowing; or may bemore gradual, as by exposure in thin films to, air, provided the oxidation is: suiiiciently prolonged to obtain the desired drasticoxidation. Usually, the time required is. atleast; about: 8 .to: 10 hours, .under conditionsmost favorable to oxidation, e. g., blowing at arelatively hightemperature, and for certain. fatty. compounds much more prolonged oxidation, e. g., several days or even weeks, is desirable, especially underconditions less favorable to rapid oxidation. In any event, whether the oxidation is produced by continued mild oxidation, or by more vigorous oxidation, a condition of drastic oxidation is indicatedby'changes in chemical andphysical properties of the-material. These changes are usually indicated by a: lowered iodine-value,-, an increased saponification- Value, usually an increased acetyl value, an increased specific gravity, and an increased refractive index. Thus, the iodine number may become less than 70, and even as low as about 40. The saponification value may be about 215 to about 283, and the acetyl value may be about 160 to about 200. The viscosity is increased and the drastically-oxidized product may become very heavy and stiff at ordinary temperatures. The refractive index is also increased. The color of the drastically-oxidized material may be a pale yellow or light amber, or may be a deep orange color. If oxidation is carried on long enough, a product of liver-like consistency and dark color is obtained, but since such material is more diflicult to utilize, those drastically-oxidized ricinoleic compounds which are pale blown and have some fluidity at normal temperatures are preferred.

The same sort of procedure which is used to oxidize castor oil or similar ricinoleic acid derivatives, may be used to oxidize 9,11-linolo-diricinolein. Generally speaking, however, the following modification should be kept in mind.

Such material may contain a small amount of 9gl'l-linoleic acid or its ester. resulting from imcomplete polymerization. Such product'is recognized as a powerful catalyst for promoting oxidation of castor oil or similar materials. Thus, itis rarely necessary to add any catalyst to hasten oxidation. Furthermore, it is rarely necessary to oxidize under pressure, although such procedure may be employed. It is rarely necessary to useoxygen insteadof air. Although any suitable temperature, from C. or upwards may be em-- ployed, it is my preference to oxidize at a temperature of approximately C, to C. and

use a fairly long time interval, for instance, two to eight days, notwithstanding thefact that any of the usual procedures employed for oxidizing castor oil may be employed for oxidizing 9,-1-1- linolo diricinolein, and generall speaking, considerably less drastic conditions are required. The

cedure is employed as in the case of conventional.

oxidation. of castor oil. The product subjected to oxidation in the instant procedure has a viscosity somewhat greater than castor oil and seems.

longer soluble in the various solvents hereinafter enumerated, such as xylene, anhydrous isopropyl alcohol, carbon tetrachloride, cresylic acid, etc.

The iodine number of the raw material-which is subjected to oxidation approximatesthat ofcastor oil; that is, around 90. If oxidation is drastic enough, the iodine number is reduced to approximately-one-half its originalvalue. One can readily produce three; difierent grades, which, of course, show the effect of increased or more drasticox-idation. One obtains alight blown and-light bodied. material by reducing the original iodine value by approximately 25%. If oxidation is continued, or if more severe conditions of oxidation are employed, such as increased temperature, increased passage of air or addition of catalyst, one can readily reduce the iodine number by a value equivalent to 26% to 35% of the original value. Such material may be considered as a medium bodied, medium oxidized material. Similarly, more extensive oxidation or more drastic oxidation will reduce the iodine value from 36% to in excess of 50% of its original value. Such product may be considered as heavy bodied and heavily oxidized. Oxidation beyond this stage generally yields insoluble, or spongy, or rubbery masses.

In any event, the products herein contemplated are such that drastic oxidation by means of a gaseous oxygen-containing medium, results in a reduction in iodine number equivalent to at least 10% of its original value.

Light-bodied, light-blown product 9,11-linolo-diricinolein is oxidized by dry air at a temperature of 120 C. or somewhat in excess,

for approximately four to five days, or slightly longer, so as to reduce the iodine value by 25% of its original value.

Medium-bodied, moderately oxidized product The same procedure is followed as in Example 1, except that the time of oxidation is extended by approximately 2 or 3 days, and the temperature raised slightly, if need be, so that at the end of the period, the product shows a reduction in original iodine value equivalent to 33 /3% and an increased viscosity compared with the light-blown product previously described.

H eddy-bodied, heavily-blown product The same procedure is followed as in the preceding example, except that oxidation is extended a few days longer and a somewhat higher temperature employed, if need be, so as to reduce the iodine value by a percentage equivalent to almost one-half its original value.

The new chemical products or compounds herein described, are useful for other purposes in addition to demulsification. They may be added in saponified form, for example, to many polishes to help emulsification. They may also be employed as a plasticizer in resin formation, where the acidity of the slight carboxyl is not objectionable.

I have found that the chemical compounds herein described which are particularly desirable for use as demulsifiers, may also be used as break inducers in doctor treatment of the kind intended to sweeten gasoline. (See U. S. Patent No. 2,157,223, dated Ma 9, 1939, to Sutton.)

In the hereto appended claims the product contemplated is described in terms of method of manufacture. The reason is obviously the same reason that makes it impossible to describe blown castor oil by structural formula or combination of structural formulas. In the first place, a variety of products are formed during oxidation, and in many instances, such products either have not been identified at all, or have partially been identified. To a marked degree, the chemistry of oxidation of castor oil or my product, as herein described, is still obscure. It is also to be noted that such mode of description has been used repeatedly in the patent literature.

Attention is directed to my co-pending application, Serial No. 604,992, filed July 13, 1945.

Having thus described my invention, what I 8 claim as new and desire to secure by Letters Patent is:

1. In the process of manufacturing a drasticallyoxidized dimer, the step of oxidizing a dimer of the formula with an oxygen-containing gas at a temperature between and 240 C. for a period of time sufficient to produce a reduction in iodine value equivalent to at least 10 per cent of the original value and not over 50 per cent of the original value.

2. The resultant product obtained in the process described in claim 1 wherein the oxygen containing gas is air.

3. The resultant product obtained in the process described in claim 1 wherein the oxygen containing gas is air, and the reduction in iodine value is the equivalent of at least 15 per cent and not over 25 per cent of the original value.

4. The resultant product obtained in the process described in claim 1 wherein the oxygen containing gas is air, and the reduction in iodine value is the equivalent of at least 26 per cent and not over 35 per cent of the original value.

5. The resultant product obtained in the process described in claim 1 wherein the oxygen containing gas is air, and the reduction in iodine value is the equivalent of at least 36 per cent and not over 50 per cent of the original value.

MELVIN DE GROOTE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,347,562 Johnston Apr. 25, 1944 2,406,206 De Groote Aug. 20, 1946 

